The full form of SARS is "Severe Acute Respiratory Syndrome".
Severe Acute Respiratory Syndrome is an infectious viral disease caused by Coronaviruses. These coronaviruses belong to a family of large, positive, single-stranded RNA viruses. This virus has been isolated from several animals including civet cats and raccoon dogs although neither of them is regarded as a true source.
Recently certain bat species (horseshoe bats) have been reported as natural reservoirs of coronaviruses.
The most affected parts of the human body are the respiratory tract and gastrointestinal tract in SARS. The damage caused by coronaviruses in SARS is seen more in the lower respiratory tract.
The SARS coronavirus targets the epithelial cells of the respiratory tract, resulting in diffuse alveolar damage.
Several organs/cell types may be infected in the course of the illness, including mucosal cells of the intestines, tubular epithelial cells of the kidneys, neurons of the brain, and several types of immune cells, and certain organs may suffer from indirect injury.